Since he's been tweeting the return of the old cast's names in doubles and triples (with the exception of Hugh), I think he may sandwich her announcement with that of 1 or 2 other big names.

I do wonder if January Jones is returning. She did nothing for me as Emma Frost (Alice Eve was born for the role) so I can't say I'll be disappointed if he skips her altogether. However, I won't be terribly upset if he does cast January either. I love her as an actress, just not as the White Queen.